MALDI Mass Spectrometry Imaging of N-Linked Glycans in Cancer Tissues.

Glycosylated proteins account for a majority of the posttranslation modifications of cell surface, secreted, and circulating proteins. Within the tumor microenvironment, the presence of immune cells, extracellular matrix proteins, cell surface receptors, and interactions between stroma and tumor cells are all processes mediated by glycan binding and recognition reactions. Changes in glycosylation during tumorigenesis are well documented to occur and affect all of these associated adhesion and regulatory functions. A MALDI imaging mass spectrometry (MALDI-IMS) workflow for profiling N-linked glycan distributions in fresh/frozen tissues and formalin-fixed paraffin-embedded tissues has recently been developed. The key to the approach is the application of a molecular coating of peptide-N-glycosidase to tissues, an enzyme that cleaves asparagine-linked glycans from their protein carrier. The released N-linked glycans can then be analyzed by MALDI-IMS directly on tissue. Generally 40 or more individual glycan structures are routinely detected, and when combined with histopathology localizations, tumor-specific glycans are readily grouped relative to nontumor regions and other structural features. This technique is a recent development and new approach in glycobiology and mass spectrometry imaging research methodology; thus, potential uses such as tumor-specific glycan biomarker panels and other applications are discussed.

Hand dominance and performance in a laparoscopic skills curriculum.

BACKGROUND: This study evaluated the influence of hand dominance on skill acquisition during a basic laparoscopic skills curriculum. METHODS: A total of 27 surgical residents (5 postgraduate year 3 [PGY-3] and 22 PGY-2 residents) participated in a 4-week laparoscopic skills curriculum. The residents were pre- and posttested on six laparoscopic tasks during weeks 1 and 4. During weeks 2 and 3, the residents attended a proctored practice session. The results were compared using analysis of variance (ANOVA), (with significance determined by a p value less than 0.05. RESULTS: The posttest scores were significantly higher than the pretest scores. On the pretest, lefthand-dominant (LHD) surgeons (n = 4) performed significantly better than righthand-dominant (RHD) surgeons (n = 23). In the analysis of individual task pretest scores, LHD surgeons performed significantly better on pattern cutting and vessel loop application. Posttest analysis of overall performance did not show significant differences between the RHD and LHD surgeons. CONCLUSIONS: Participation in a laparoscopic skills curriculum improved overall performance. The LHD surgeons demonstrated better initial performance, but posttest comparison showed no difference between the two groups.

Ureteral injury in gynecologic surgery: a ten-year review in a community hospital.

OBJECTIVE: Our purpose was to review and analyze ureteral injuries incidental to gynecologic surgery in a community hospital. STUDY DESIGN: During the study period from Jan. 1, 1983, through Dec. 31, 1992, all patient records in which ureteral injury resulted from gynecologic surgery were reviewed. The operative procedure, pathologic result, location of injury, and type of repair were studied. Additionally, the time of recognition and diagnostic methods in these ureteral injuries were analyzed. RESULTS: Nineteen ureteral injuries were incurred during the performance of 4665 gynecologic surgical procedures, an incidence of 0.4%. Patients ranged in age from 23 to 70 years. Recognition of the ureteral injury occurred intraoperatively in 10 patients and was delayed from 1 to 16 days in 9 patients. Six of the ureteral injuries were repaired by end-to-end anastomosis, 3 by deligation, and 10 by ureteroneocystostomy. Immediate postoperative urinary integrity was found in all patients. CONCLUSION: Gynecologic surgical procedures in this study resulted in a 0.4% incidence of ureteral injury, and repair of these injuries was successful in all cases for the short term.

The outpatient vaginal hysterectomy.

OBJECTIVE: The purpose of our study is to report on our initial experience with the performance of vaginal hysterectomy on an outpatient basis. STUDY DESIGN: Between January 1990 and February 1992 10 patients underwent vaginal hysterectomies in a freestanding outpatient surgery center. All patients were discharged the same day within 8 hours of the starting time of surgery. Patients ranged in age from 32 to 52 years and had no major medical problems. Concomitant salpingo-oophorectomies, enterocele repairs, or both were also performed on 8 of the 10 patients. RESULTS: All patients had benign diseases, and the uteri weighed between 75 and 142 gm. There were no intraoperative complications, and 9 of the 10 patients had an uneventful postoperative course. Although postoperative pain control was not a problem, there was some degree of postoperative nausea during the first 24 hours associated with the use of various oral and transcutaneous analgesics. Nonetheless, all 10 patients were pleased with their surgical experience. CONCLUSION: This small pilot study adds to the growing body of literature that demonstrates the safety and feasibility of performing vaginal hysterectomy (together with certain concomitant procedures) in an outpatient setting.

Modified retropubic cystourethropexy. II.

In 1986 we published a preliminary report describing a modification for bladder-neck suspension in the treatment of urinary stress incontinence. From 1982 through 1989 135 surgical procedures were performed. Long-term follow-up of these patients is now presented. Of the 135 patients in this study, 118 were available for follow-up at the time of this report; 108 (91.5%) of the 118 reported no urinary leakage. Of the 10 patients who reported continued urinary leakage, only 2 had persistent or recurrent urinary stress incontinence; they were reoperated on with favorable results. The other eight patients reporting urinary leakage were patients with mixed-cause urgency incontinence. The adjusted success rate for the treatment of genuine stress incontinence was therefore 98%.

Modified retropubic cystourethropexy.

A variation of retropubic suspension of the urethrovesical junction was performed on 26 patients with urinary stress incontinence. Access to the retropubic space was through a low transverse muscle-splitting incision. Surgical technique consisted of securing a helical Prolene suture in the paraurethral fascia at each side of the bladder neck. Each suture was then passed through the abdominal wall fascia, exiting just above the symphysis pubis on either side of the midline, and tied to the opposite suture above the rectus fascia. The desired amount of elevation of the vesical neck was gauged by a Q-tip applicator inserted into the urethra just before the Prolene sutures were tied down. A cystotomy was performed to rule out any inadvertent penetration of the bladder by the nonabsorbable suture material, and the bladder was drained suprapubicly. The small number of cases and short follow-up times do not allow conclusions to be drawn at this time, but results to date have been encouraging.